Section 1: Scientific method Section 2: Units of measurement Section 3: Using scientific measurements
Section 1 Vocabulary:
Scientific Method - A logical approach to solving problems by observing and collecting data, formulating hypotheses, testing hypotheses, and formulating theories that are supported by data. Hypothesis - A testable statement. Theory - A theory is a broad generalization that explains a body of known facts or phenomena. Model - In science a model is more than just a physical object; it is an explanation of how phenomena occur and how data or events are related.
Section 2 Vocabuary:
Quantity - Something that has magnitude, size, or amount. Volume - The amount of space occupied by an object.
- An Example converting 1m3 to 1,000,000 cm3 Density - Is the ratio of mass to volume, or mass divided by volume. Dimensional Analysis - A mathematical technique that allows you to use units to solve problems involving measurements.
- Quantity sought = quantity given X conversion factor. Conversion Factor - A ratio derived from the equality between two different units that can be used to convert from one unit to the other.
Section 3 Vocabulary:
Accuracy - Refers to the closeness of measurements to the correct or accepted value of the quantity measured. Precision - Refers to the closeness of a set of measurements of the same quantity made in the same way. Percentage error - It’s calculated by subtracting the accepted value from the experimental value, dividing the difference by the accepted value, and then multiplying by 100.
Example problem:
Example for Percentage error: You do an experiment and find out that atomic weight for helium is 4.1 here you can see this is not correct by using the percent error equation.
Significant figures:
- In a measurement consisting of all the digits known with certainty plus one final digit, which is somewhat uncertain or is estimated.
Rules:
1. Zeros appearing between nonzero digits are significant.
2. Zeros appearing in front of all nonzero digits are not significant.
3. Zeros at the end of a number and to the right of a decimal point are significant.
4. Zeros at the end of a number but to the left of a decimal point may or may not be significant. If a zero has not been measured or estimated but is just a placeholder, it is not significant. A decimal point placed after zeros indicates that they are significant.
HINT: When adding or subtracting decimals, the answer must have the same number of digits to the right of the decimal point as there are in the measurement having the fewest digits to the right of the decimal point.
Scientific Notation- Numbers are written in the form M x 10^n, where the factor M is a number greater than or equal to 1 but less than 10 and n is a whole number.
Ex: 65000 km into scientific notation 6.5 x 104 km
Direct Proportions - Two quantities are directly proportional to each other if dividing one by the other gives a constant value. Inverse Proportions - Two quantities are inversely proportional to each other if their product is constant.
Chapter Two
Section 1: Scientific method
Section 2: Units of measurement
Section 3: Using scientific measurements
Section 1 Vocabulary:
Scientific Method - A logical approach to solving problems by observing and collecting data, formulating hypotheses, testing hypotheses, and formulating theories that are supported by data.
Hypothesis - A testable statement.
Theory - A theory is a broad generalization that explains a body of known facts or phenomena.
Model - In science a model is more than just a physical object; it is an explanation of how phenomena occur and how data or events are related.
Section 2 Vocabuary:
Quantity - Something that has magnitude, size, or amount.
Volume - The amount of space occupied by an object.
- An Example converting 1m3 to 1,000,000 cm3
Density - Is the ratio of mass to volume, or mass divided by volume.
Dimensional Analysis - A mathematical technique that allows you to use units to solve problems involving measurements.
- Quantity sought = quantity given X conversion factor.
Conversion Factor - A ratio derived from the equality between two different units that can be used to convert from one unit to the other.
Section 3 Vocabulary:
Accuracy - Refers to the closeness of measurements to the correct or accepted value of the quantity measured.
Precision - Refers to the closeness of a set of measurements of the same quantity made in the same way.
Percentage error - It’s calculated by subtracting the accepted value from the experimental value, dividing the difference by the accepted value, and then multiplying by 100.
Example problem:
Example for Percentage error: You do an experiment and find out that atomic weight for helium is 4.1 here you can see this is not correct by using the percent error equation.Significant figures:
- In a measurement consisting of all the digits known with certainty plus one final digit, which is somewhat uncertain or is estimated.Rules:
1. Zeros appearing between nonzero digits are significant.2. Zeros appearing in front of all nonzero digits are not significant.
3. Zeros at the end of a number and to the right of a decimal point are significant.
4. Zeros at the end of a number but to the left of a decimal point may or may not be significant. If a zero has not been measured or estimated but is just a placeholder, it is not significant. A decimal point placed after zeros indicates that they are significant.
HINT:
When adding or subtracting decimals, the answer must have the same number of digits to the right of the decimal point as there are in the measurement having the fewest digits to the right of the decimal point.
Scientific Notation- Numbers are written in the form M x 10^n, where the factor M is a number greater than or equal to 1 but less than 10 and n is a whole number.
Ex: 65000 km into scientific notation 6.5 x 104 km
Direct Proportions - Two quantities are directly proportional to each other if dividing one by the other gives a constant value.
Inverse Proportions - Two quantities are inversely proportional to each other if their product is constant.
Peter Hric
Jesse Nowak
Period 6
Mr. Ptachcinski